Background. The antiangiogenic properties of shark cartilage extracts have
been demonstrated in animal models but there are no data in human subjects.
Materials and methods. A placebo or one of two doses of a liquid shark cart
ilage extract was orally administered daily, from Day 1 to Day 23 of the st
udy protocol, to 29 healthy male volunteers randomized into three groups. O
n Day 12, a polyvinyl alcohol sponge threaded in a perforated silicone tubi
ng was inserted subcutaneously on the anterior side of the arm and removed
on Day 23. Evaluation of endothelial cell density, with factor VIII immunos
taining, an indirect measurement of angiogenesis, was performed on histolog
ical sections of the implant using a semiquantitative numerical scale rangi
ng from 1 (low density) to 5 thigh density). The hydroxyproline content of
the sponges was measured by HPLC.
Results. The mean endothelial cell density was significantly lower in group
s that had received the liquid cartilage extract: grades 2.24 +/- 0.10, 2.4
7 +/- 0.10, and 3.15 +/- 0.11 for 7 and 21 mi liquid cartilage extract and
placebo, respectively (P < 0.01 for both comparisons). No grade 1 was obser
ved in the placebo group, whereas 9 treated subjects received a grade 1. Hy
droxyproline content of the sponges did not differ between groups and there
was no significant correlation between hydroxyproline content and endothel
ial cell density in the sponges.
Conclusions. These results demonstrate that the liquid cartilage extract co
ntains an antiangiogenic component bioavailable in humans by oral administr
ation.
This is the first report of an inhibition of wound angiogenesis in healthy
men. (C) 1999 Academic Press.